JPH0771882B2 - Castor device - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a caster device such as a moving carriage, and more particularly to a caster device having a spherical outer appearance.

[Technical Background of the Invention and Problems Thereof] A caster device such as a moving carriage is eccentrically located on a first rotating shaft rotatably and vertically supported by the moving carriage from the rotation axis of the first rotating shaft. Generally, a horizontal second shaft is provided at a position, and a roller is rotatably supported on the second shaft.
In such a configuration, the moving direction of the moving carriage and the second
When the axes are orthogonal to each other, the rollers rotate smoothly. In the above state, after stopping the movement of the movable carriage, when the movable carriage is directed to move in the direction (parallel to the second axis) orthogonal to the moving direction up to now, the contact of the roller is made. With the radius between the point and the axis of rotation of the first rotary shaft, the movable carriage makes an eccentric movement around the ground contact point, and the second shaft becomes orthogonal to the moving direction of the movable carriage again.

That is, in the conventional caster device using the rollers, when the moving direction of the moving carriage is changed, a large eccentric motion occurs in the moving carriage, and it is difficult to stabilize the directionality of the moving carriage. Therefore, in the case of, for example, a self-propelled mobile cart, it is difficult to accurately control in the command direction from the control device due to the eccentric movement.

[Object of the Invention] The present invention has been made in view of the conventional problems as described above, and an object thereof is to control the eccentric movement given to the moving carriage when converting the moving direction of the moving carriage to the direction of the moving carriage. An object of the present invention is to provide a novel castor device that can maintain the property and easily change the direction.

[Summary of the Invention] In order to achieve the above-mentioned object, the present invention provides a first rotating shaft mounted on a moving carriage vertically and rotatably around an axis, and provided on an outer peripheral surface of a disk member. The two rotary shafts are horizontally supported and provided on the first rotary shaft at positions eccentrically located from the axial center position of the first rotary shaft, and the disc member is rotatably provided around the axial center of the second rotary shaft. A hemisphere having substantially the same diameter as the diameter of the disk member is provided at both ends of a third shaft that penetrates the axis of the disk member, and each hemisphere is rotatably provided around the axis of the third shaft. At the same time, the disk member and each hemisphere form a spherical body, and the directionality of the moving carriage (1) is kept constant by the rotation of the first, second and third rotating shafts. The configuration is such that the moving direction can be changed easily and smoothly.

[Embodiment of the Invention] Referring to FIGS. 1 and 2, a rotary plate 5 is horizontally rotatably supported by a bearing 3 at a central portion of a lower surface of a movable carriage 1. At the position close to
A rotation regulating device 7 capable of regulating the rotation of is mounted.
The rotation restricting device 7 is composed of, for example, an appropriate clamp device that can hold the peripheral edge of the rotating plate 5 and the like, and allows the rotating plate 5 to rotate and to stop the rotating plate 5 from rotating. It is what makes up.

Drive motors 9A and 9B, such as a pulse motor and a servo motor, which can rotate normally and reversely, are mounted at symmetrical positions of the rotary plate 5, and the drive shafts 11A are normally and reversely rotated by the drive motors 9A and 9B. , 11B are provided with traveling wheels 13A, 13B, respectively.

As can be understood from the above-described configuration, the drive wheels 9A and 13B are controlled by appropriately controlling the drive motors 9A and 9B in a state where the rotary plate 5 is integrally fixed to the movable carriage 1 by the rotation restricting device 7. By rotating the same direction in the same direction,
The moving carriage 1 moves linearly. Further, by imparting a rotation difference to the traveling wheels 13A and 13B, the moving carriage 1 turns right or left to change the direction. Further, when the traveling wheels 13A and 13B are rotated in the same direction in opposite directions, the moving carriage 1 rotates about the center of the rotary plate 5.

In addition, the fixation of the rotary plate 5 by the rotation restricting device 7 is released,
When the rotary plate 5 is freely rotatable with respect to the moving carriage 1, when the traveling wheels 13A and 13B are appropriately rotated by appropriately controlling the above-described driving motors 9A and 9B, the rotating plate with respect to the movable carriage 1 is rotated. 5 will rotate appropriately. In this case, since the frictional resistance between the rotary plate 5 and the movable carriage 1 is not strictly zero, the movable carriage 1 tends to rotate following the rotation of the rotary plate 5, but the caster device described later is used. Therefore, the movable carriage 1 does not rotate largely due to the ground resistance.

In order to support the movable carriage 1 in a stable posture, a plurality of locations on the lower surface of the movable carriage 1 (four locations in this embodiment)
The support legs 15 are vertically provided at the lower ends of the support legs 15, and the first rotary shafts 17 are rotatably provided at the lower portions of the support legs 15 via bearings. An inverted U-shaped yoke bracket 19 is integrally attached to the lower portion of each first rotary shaft 17, and a horizontal second rotary shaft orthogonal to the first rotary shaft 17 is attached to the yoke bracket 19.
A disk member 22 having an outer peripheral portion 21 is rotatably supported via a bearing. The second rotary shaft 21 is the first rotary shaft 17
Is eccentrically located at a position appropriately separated from the shaft center 17A.

A through hole 23 in a direction orthogonal to the longitudinal direction of the second rotating shaft 21 is formed in the central portion of the second rotating shaft 21 in the longitudinal direction (axial center of the disc member 22). In this through hole 23, the third shaft 25
Is rotatably supported via a bearing, and hemispheres 27A and 27B are integrally attached to both ends of the third shaft 25. That is, the hemispheres 27A and 27B are rotatably provided around the axis of the third shaft provided orthogonal to the second rotation shaft 21. More specifically, by arranging the hemispheres 27A and 27B so as to face each other on both sides of the disk member 22, a spherical body 29 is formed as a whole, and the spherical body 29 is rotatable around the second rotation shaft 21. , And is rotatably provided around the third shaft 25.

In the above configuration, the second rotary shaft 21 and the third rotary shaft 21
When the intersection point P of the straight line L orthogonal to the axis of the shaft 25 and the surface of the spherical body 29 and the intersection points Q and R of the axis of the third shaft 25 and the surface of the spherical body 29 are grounded, It is difficult to rotate the spherical body 29 around the shaft 25. But the sphere 29
And the traveling surface of the movable carriage 1 are logically point contacts, and the frictional resistance is extremely smaller than that of the conventional roller structure. Therefore, the slight movement of the movable carriage 1 is smooth, and when the intersections P, Q, and R are slightly separated from the traveling surface by this slight movement, the spherical body 29 can rotate about the third axis 25. Become. Therefore, the spherical body 29 can be easily rotated in the moving direction of the moving carriage 1, and the followability with respect to the moving carriage 1 is improved. That is, for example, the mobile carriage 1
After linearly moving, when moving the moving carriage 1 in the direction orthogonal to the moving direction so far,
Since the spherical body 29 immediately rotates in the same direction following the movement of the movable carriage 1, the movable carriage 1 does not largely move eccentrically around the ground contact point of the spherical body 29. Therefore, it is possible to easily change the moving direction of the movable carriage 1 while maintaining the directionality of the movable carriage 1.

[Effects of the Invention] As will be understood from the above description of the embodiments, in short, the present invention provides the first rotary shaft 17 mounted on the movable carriage 1 vertically and rotatably around the axis, and the disk member. A second rotary shaft 21 provided on the outer peripheral surface of 22 is horizontally supported and provided on the first rotary shaft 17 at a position eccentrically located from the axial center position of the first rotary shaft 17, and the disc member 22 is provided with the second rotary shaft 21. 2 rotation axes
21 is provided rotatably around the axis of the disk member 22, and hemispheres 27A and 27B having a diameter substantially the same as the diameter of the disk member 22 are provided on both ends of the third shaft 25 penetrating the axis of the disk member 22. The hemispheres 27A and 27B are rotatably provided around the axis of the third shaft 25, and the disk member 22 and the hemispheres 27A and 27B form a spherical body 29. By the rotation of the third rotating shaft, it is possible to easily and smoothly change the moving direction while keeping the directionality of the moving carriage 1 constant.

As is apparent from the above-mentioned configuration, in the present invention, the horizontal second rotary shaft 21 which is orthogonal to the vertical first rotary shaft 17 attached to the movable carriage 1 and is unevenly distributed on the outer peripheral surface of the disk member 22. The third shaft 25 is provided so as to penetrate the axis of the disk member 22. By providing hemispheres 27A and 27B on both ends of the third shaft 25, the disk member 22 and the hemispheres 27A and 27B form a spherical body 29. And the first,
The rotation of the second and third rotation shafts makes it possible to easily and smoothly change the moving direction while keeping the directionality of the moving carriage 1 constant.

Therefore, according to the present name, for example, when the movable carriage 1 moves in the front-rear direction, the spherical body 29 rotates around the second rotation axis 21 to move the movable carriage 1 and then the directionality of the movable carriage 1 is increased. Is kept constant, for example, when the moving direction is changed to the left-right direction, even if a part of the outer peripheral surface of the disk member 22 is in the grounded state, the first rotating shaft 17 slightly rotates to cause the hemisphere. Since the bodies 27A and 27B are grounded and rotate about the third shaft 25, and the second rotation shaft 21 is orthogonal to the moving direction, the first, second and third rotation shafts are Each of them can rotate so that the moving carriage 1 can be smoothly moved.

[Brief description of drawings]

FIG. 1 is a front view of a moving carriage embodying the present invention, FIG. 2 is a bottom view of the same, FIG. 3 is an enlarged sectional view taken along line III-III in FIG. 2, and FIG. 4 is IV of FIG. FIG. 5 is a perspective view schematically showing the main part, taken along the line IV-IV. 1 ... movable carriage, 17 ... first rotary shaft 21 ... second rotary shaft, 25 ... third shaft 27A, 27B ... hemisphere

Claims (1)

[Claims] 1. A first rotating shaft 17 mounted on a movable carriage 1 is provided vertically and rotatably around an axis, and a second rotating shaft 21 provided on an outer peripheral surface of a disk member 22 is provided with the first rotating shaft 17. Is provided so as to be horizontally supported by the first rotating shaft 17 at a position eccentrically located from the axial center position of the second rotating shaft 21.
Is provided rotatably around the axis of the disk member 22, and hemispheres 27A and 27B having substantially the same diameter as the diameter of the disk member 22 are provided on both ends of the third shaft 25 penetrating the axis of the disk member 22. The bodies 27A and 27B are rotatably provided around the axis of the third shaft 25, and the disk member 22 and the respective hemispheres 27A and 27B form a spherical body 29. A caster device having a configuration in which the direction of the moving carriage 1 is kept constant by the rotation of the rotary shaft 3 so that the moving direction can be easily and smoothly changed.